JP2018036953A - Communication system, communication method, media relay server, and media relay program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress the influence of a communication failure caused by a failure of a processing server.SOLUTION: A first call control server 2a controls real-time communication between a first communication terminal 7a and a second communication terminal 7b. A media relay server 1 comprises: relay means 23 which, in real-time communication, relays communication data transmitted and received between the first communication terminal 7a and the first call control server 2a, and also relays communication data transmitted and received between the second communication terminal 7b and the first call control server 2a; and termination means 24 which, when a failure occurs on the first call control server 2a, terminates communication data transmitted and received between the first communication terminal 7a and the first call control server 2a to transmit the data to the second communication terminal 7b, and also terminates communication data transmitted and received between the second communication terminal 7b and the first call control server 2a to transmit the data to the first communication terminal 7a.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a communication system that controls real-time communication between a first communication terminal and a second communication terminal, a communication method used in the communication system, a media relay server, and a media relay program.

  As a method for improving the processing capability of a server, in a system including a plurality of servers, a technique for distributing the processing to the plurality of servers is widely used (for example, see Non-Patent Document 1 and Non-Patent Document 2).

  In the distributed systems described in these non-patent documents, the load balancer receives the data transmitted by the client in a batch. The load balancer transmits data to an arbitrary distribution server, and the distribution server inputs the data to a processing server specified based on a key, a hash algorithm, and the like included in the data. In such a technique, data having the same key is processed in a specific processing server. Therefore, by setting the same key for data used for a series of processes such as from the start of a call to the end of a call, a specific processing server can process a series of data consistently.

Michio Irie, Gosei Nishimura, Masashi Kaneko, Toshikazu Bessho, Masami Iio, “Cluster model of session control server that realizes scale-out and flexible configuration change”, [online], February 28, 2011, General Incorporated Association The Institute of Electronics, Information and Communication Engineers, [August 31, 2016 search], Internet <URL: https://www.ieice.org/jpn/event/taikaiarchives/show.php/2011G/pdf/b/b_06_011.pdf> Hiroshi Noguchi, Toshiyuki Moriya, Takeshi Fukumoto, "A Study on Highly Available Server Cluster Configuration in Wide Area Network", [online], March 4, 2014, The Institute of Electronics, Information and Communication Engineers, [August 2016 31 days search], Internet <URL: https://www.ieice.org/jpn/event/taikaiarchives/show.php/2014G/pdf/b_06_104.pdf>

  However, in the distributed system described in the non-patent document, when transmitting and receiving real-time data such as voice and video, there is a problem that smooth communication cannot be realized when a failure occurs in the processing server.

  Specifically, when a failure occurs in a physical server that implements a call control function and a function for terminating real-time data, an alternative server uses SIP (Session Initiation) to notify its communication terminal of its own IP address, port number, and the like. Protocol) message. Since the communication terminal continues to send data to the physical server where the failure has occurred until it receives an IP address or the like from the alternative server, real-time data is not transmitted and received during communication between the communication terminals, resulting in a silent period. Become.

  Accordingly, an object of the present invention is to provide a communication system, a communication method, a media relay server, and a media relay program that suppress the influence of a communication failure accompanying a failure of a processing server in a distributed system in which a plurality of processing servers perform processing in a distributed manner. That is.

  In order to solve the above problems, a first feature of the present invention is that a first call control server that controls real-time communication between a first communication terminal and a second communication terminal, and real-time when a failure occurs in the first call control server. The present invention relates to a communication system including a second call control server for controlling communication, a first call control server, and a media relay server connected to the second call control server. The first call control server of the communication system according to the first aspect of the present invention controls real-time communication between the first communication terminal and the second communication terminal. The media relay server relays communication data transmitted and received between the first communication terminal and the first call control server and relays communication data transmitted and received between the second communication terminal and the first call control server in real-time communication. When a failure occurs in the relay means and the first call control server, the communication data transmitted and received between the first communication terminal and the first call control server is terminated and transmitted to the second communication terminal, and the second communication Terminating means for terminating communication data transmitted / received between the terminal and the first call control server and transmitting the data to the first communication terminal. After the failure of the first call control server, the second call control server performs real-time communication. When the control becomes possible, the termination unit terminates the termination of the communication data, and the relay unit relays the communication data transmitted and received between the first communication terminal and the second call control server. Both relays communication data transmitted between the second communication terminal and the second call control server.

  The communication system includes a standby media relay server having the same IP address as that of the media relay server. When a failure occurs in the media relay server, the standby media relay server may relay or terminate the communication data. .

  The second feature of the present invention is that a first call control server that controls real-time communication between the first communication terminal and the second communication terminal, and second call control that controls real-time communication when a failure occurs in the first call control server. The present invention relates to a communication method used in a communication system including a server and a media relay server connected to a first call control server and a second call control server. In the communication method according to the second aspect of the present invention, the media relay server relays communication data transmitted and received between the first communication terminal and the first call control server in real-time communication, and the second communication terminal and the second communication terminal A step of relaying communication data transmitted / received between one call control server, a step of the first call control server controlling real-time communication between the first communication terminal and the second communication terminal, and a failure in the first call control server. When it occurs, the media relay server terminates communication data transmitted / received between the first communication terminal and the first call control server, transmits the data to the second communication terminal, and between the second communication terminal and the first call control server. Terminating the communication data transmitted / received at the first communication terminal and transmitting it to the first communication terminal, and after the failure of the first call control server, the second call control server performs real-time communication. When it becomes possible, the media relay server terminates the termination of the communication data, relays the communication data transmitted and received between the first communication terminal and the second call control server, and the second communication terminal and the second call control server. A step of relaying communication data transmitted and received between them.

  A third feature of the present invention is used in a communication system including a first call control server that controls real-time communication between a first communication terminal and a second communication terminal, and a media relay server connected to the first call control server. The media relay server. The media relay server according to the third aspect of the present invention relays communication data transmitted and received between the first communication terminal and the first call control server in real-time communication, and the second communication terminal and the first call control server. When a failure occurs in the first call control server and the relay means for relaying communication data transmitted / received between the first communication terminal and the second communication, the communication data transmitted / received between the first communication terminal and the first call control server is terminated. Termination means is provided that terminates communication data transmitted and received between the second communication terminal and the first call control server and transmits the data to the first communication terminal.

  Here, the media relay server is connected to a second call control server that controls real-time communication when a failure occurs in the first call control server, and after the failure occurs in the first call control server, the second call control server controls real-time communication. When possible, the termination unit terminates the termination of the communication data, and the relay unit relays the communication data transmitted and received between the first communication terminal and the second call control server, and the second communication terminal and the second call. You may relay the communication data transmitted / received between control servers.

  The termination means may further comprise recording means for recording the communication data while terminating the communication data.

  A fourth feature of the present invention relates to a media relay program that causes a computer to function as the means described in the third feature of the present invention.

  The present invention provides a communication system, a communication method, a media relay server, and a media relay program that suppress the influence of a communication failure accompanying a failure of a processing server in a distributed system in which a plurality of processing servers perform processing in a distributed manner. Can do.

FIG. 1 is a diagram illustrating a system configuration of a communication system according to an embodiment of the present invention. FIG. 2 is a diagram illustrating a case where the first call control server controls communication between the first communication terminal and the second communication terminal. FIG. 3 is a diagram illustrating a case where the media relay server terminates communication between the first communication terminal and the second communication terminal. FIG. 4 is a diagram illustrating a case where the second call control server controls communication between the first communication terminal and the second communication terminal. FIG. 5 is a sequence diagram for explaining a communication method according to the embodiment of the present invention (part 1). FIG. 6 is a sequence diagram for explaining a communication method according to the embodiment of the present invention (part 2). FIG. 7 is a diagram for explaining the hardware configuration and functional blocks of the media relay server according to the embodiment of the present invention. FIG. 8 is a diagram for explaining an example of the data structure and data of the setting data of the media relay server. FIG. 9 is a diagram illustrating a multiplex configuration of a media relay server according to a modification. FIG. 10 is a diagram for explaining the hardware configuration and functional blocks of a media relay server according to a modification.

  Next, embodiments of the present invention will be described with reference to the drawings. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals.

(Communications system)
A communication system 9 according to an embodiment of the present invention will be described with reference to FIG. The communication system 9 includes a communication control system 6, a first communication terminal 7a, a second communication terminal 7b, and a web server 8. The communication control system 6, the first communication terminal 7a, the second communication terminal 7b, and the web server 8 are connected to be communicable with each other via a communication network.

  In the embodiment of the present invention, the first communication terminal 7a and the second communication terminal 7b perform real-time communication such as voice and video using C2D (Click to Dial) that realizes a two-party call via a web browser. The case where it performs is demonstrated.

  The web server 8 provides a web screen to the first communication terminal 7a and the second communication terminal 7b.

  The 1st communication terminal 7a and the 2nd communication terminal 7b are communication terminals which a speaker uses, Comprising: A telephone, a smart phone, etc. are assumed. In the embodiment of the present invention, a case will be described in which the first communication terminal 7a is used by a general user, and the second communication terminal 7b is used by an operator who responds to a general user's inquiry.

  In C2D, for example, the first communication terminal 7a inputs its own telephone number on an inquiry screen provided by the web server 8, and clicks an “inquiry” button. Thereafter, the web server 8 notifies the communication control system 6 of the telephone number of the first communication terminal 7a. As a first call, the communication control system 6 transmits an INVITE message to the first communication terminal 7a in order to realize an RTP (Real-time Transport Protocol) connection with the first communication terminal 7a. A 200 OK message is received from 7a. Further, the communication control system 6 transmits an INVITE message to the second communication terminal 7b and receives a 200OK message from the second communication terminal 7b in order to realize the RTP connection with the second communication terminal 7b as the second call. To do. Thereafter, the communication control system 6 relays the RTP connection with the first communication terminal 7a and the RTP connection with the second communication terminal 7b to realize real-time communication between the first communication terminal 7a and the second communication terminal 7b. .

  In the embodiment, call control in C2D will be described, but the present invention is not limited to this. For example, the embodiment of the present invention can be applied to a normal call in which the first communication terminal 7a makes a call and the second communication terminal 7b receives a call.

(Call control system)
As shown in FIG. 1, the communication control system 6 includes a media relay server 1, a first call control server 2a, a second call control server 2b, a first storage device 3a, a second storage device 3b, and a first distribution server 4a. The second distribution server 4b and the load balance server 5 are provided.

  The load balance server 5 is connected to the first communication terminal 7a, the second communication terminal 7b, and the web server 8 via a communication network. The load balance server 5 inputs a signal received from the first communication terminal 7a, the second communication terminal 7b, and the web server 8 to any distribution server of the first distribution server 4a and the second distribution server 4b. To do. Further, the signal received from the media relay server 1 is transmitted to the communication network.

  Based on the identifier included in the signal received from the load balance server 5, the first distribution server 4a and the second distribution server 4b send a signal to the call control server that processes the signal via the media relay server 1. Send.

  In the embodiment of the present invention, in the real-time communication between the first communication terminal 7a and the second communication terminal 7b, the first call control server 2a controls the real-time communication by assigning a common identifier. Is possible.

  The first call control server 2a and the second call control server 2b control calls and communications between communication terminals. In the embodiment of the present invention, the first call control server 2a controls real-time communication between the first communication terminal 7a and the second communication terminal 7b. The second call control server 2b functions as an alternative device when a failure occurs in the first call control server 2a. The first storage device 3a and the second storage device 3b store data such as call information that is referred to and updated by the first call control server 2a and the second call control server 2b, respectively. Between the first call control server 2a and the second call control server 2b, the call information held by each is shared and prepared to be an alternative machine when a failure occurs.

  The media relay server 1 relays communication data related to real-time communication transmitted and received between the first communication terminal 7a, the second communication terminal 7b, and the first call control server 2a or the second call control server 2b. The media relay server 1 transmits the signals transmitted by the first distribution server 4a and the second distribution server 4b to the first call control server 2a or the second call control server 2b. The media relay server 1 sends the signal received from the first call control server 2a or the second call control server 2b to the communication network via the load balance server 5.

(Overview)
The outline of the present invention will be described with reference to FIGS.

  FIG. 2 illustrates a case where the first call control server 2a controls communication between the first communication terminal 7a and the second communication terminal 7b. As shown in FIG. 2, the first communication terminal 7a has an IP address of 192.168.10. aaa, use port 10000 for first call downstream RTPT1. The second communication terminal 7b has an IP address of 192.168.10. bbb, which uses port 20000 for the second call downstream RTPT2. The first call control server 2a has an IP address of 192.168.10. fff, using port 60000 for the first call RTPT3 and using port 60010 for the second call RTPT4. The media relay server 1 has an IP address of 192.168.10. eee, port 50000 is used to relay the first call downstream RTPT1 and the first call RTPT3, and port 50010 is used to relay the second call downstream RTPT2 and the second call RTPT4.

  FIG. 3 illustrates a case where a failure occurs in the first call control server 2a. When a failure occurs in the first call control server 2a, the media relay server 1 terminates data related to real-time communication. The media relay server 1 transmits the data received at the first call downstream side RTPT1 of the port 50000 to the second call downstream side RTPT2 of the port 50010 without transmitting it to the first call control server 2a. Similarly, the media relay server 1 transmits the data received at the second call downstream side RTPT2 of the port 50010 to the first call downstream side RTPT1 of the port 50000 without transmitting the data to the first call control server 2a.

  Meanwhile, the second call control server 2b prepares to function as an alternative to the first call control server 2a. The second call control server 2b transmits an INVITE message for the first call and the second call to the media relay server 1, respectively. When the 200OK message is received for each INVITE message from the media relay server 1, the second call control server 2b operates as an alternative to the first call control server 2a.

  FIG. 4 illustrates a case where the second call control server 2b controls communication between the first communication terminal 7a and the second communication terminal 7b. The second call control server 2b has an IP address of 192.168.10. ggg, using port 70000 for the new first call RTPT5 and using port 70010 for the new second call RTPT6. The media relay server 1 uses the port 50000 to relay the first call downstream RTPT1 and the new first call RTPT5, and uses the port 50010 to relay the second call downstream RTPT2 and the new second call RTPT6. Use.

(Communication method)
With reference to FIG. 5 and FIG. 6, the communication method according to the embodiment of the present invention will be described. FIG. 5 discloses a process after the first communication terminal 7a inputs the telephone number of the first communication terminal via the web server 8, and the web server 8 inputs the telephone number to the first call control server 2a. To do.

  In step S1, the first call control server 2a transmits an INVITE message F1 to the media relay server 1. The INVITE message F1 is described based on SDP, and the IP address of the first call control server 2a and the port number for the first call are set.

  In step S2, the media relay server 1 transmits an INVITE message F2 to the first communication terminal 7a via the load balance server 5. In the INVITE message F2, the IP address of the media relay server 1 and the port number for the first call are set.

  In step S <b> 3, the first communication terminal 7 a transmits a 200 OK message F <b> 3 to the media relay server 1 via the load balance server 5. In the 200 OK message F3, the IP address of the first communication terminal 7a and the port number for the first call are set.

  In step S4, the media relay server 1 transmits a 200 OK message F4 to the first call control server 2a. In the 200 OK message F4, the IP address of the media relay server 1 and the port number for the first call are set.

  In step S5, the first call control server 2a transmits an INVITE message F5 to the media relay server 1. In this INVITE message F5, the IP address of the first call control server 2a and the port number for the second call are set.

  In step S6, the media relay server 1 transmits the INVITE message F6 to the second communication terminal 7b via the load balance server 5. In the INVITE message F6, the IP address of the media relay server 1 and the port number for the second call are set.

  In step S <b> 7, the second communication terminal 7 b transmits a 200 OK message F <b> 7 to the media relay server 1 via the load balance server 5. In the 200 OK message F7, the IP address of the second communication terminal 7b and the port number for the second call are set.

  In step S8, the media relay server 1 transmits a 200 OK message F8 to the first call control server 2a. In the 200 OK message F8, the IP address of the media relay server 1 and the port number for the second call are set.

  As shown in FIG. 2, the first call downstream RTPT1, the second call downstream RTPT2, the first call RTPT3, and the second call RTPT4 are set by the processing of steps S1 to S8. The media relay server 1 relays the first call downstream RTPT1 and the first call RTPT3 using the port 50000, and relays the second call downstream RTPT2 and the second call RTPT4 using the port 50010.

  Thereafter, when a failure occurs in the first call control server 2a, the media relay server 1 starts terminating the media in step S11. Specifically, the media relay server 1 transmits the data received at the first call downstream side RTPT1 of the port 50000 to the second call downstream side RTPT2 of the port 50010. The media relay server 1 transmits the data received at the second call downstream side RTPT2 of the port 50010 to the first call downstream side RTPT1 of the port 50000. The media relay server 1 relays data with port numbers 50000 and 50010. Meanwhile, the INVITE message is transmitted from the second call control server 2b to the media relay server 1, and the second call control server 2b prepares to operate as an alternative to the first call control server 2a.

  Specifically, in step S12, the second call control server 2b transmits an INVITE message F9 to the media relay server 1. In this INVITE message F9, the IP address of the second call control server 2b and the port number for the first call are set.

  In step S13, the media relay server 1 transmits a 200 OK message F10 to the second call control server 2b. In the 200 OK message F10, the IP address of the media relay server 1 and the port number for the first call are set.

  In step S14, the second call control server 2b transmits the INVITE message F11 to the media relay server 1. In this INVITE message F11, the IP address of the second call control server 2b and the port number for the second call are set.

  In step S15, the media relay server 1 transmits a 200 OK message F12 to the second call control server 2b. In the 200 OK message F12, the IP address of the media relay server 1 and the port number for the second call are set.

  When the media relay server 1 transmits the 200 OK message for each of the first call and the second call, in step S16, the media relay server 1 ends the termination of the media. Thereafter, the media relay server 1 relays the first call downstream RTPT1 and the new first call RTPT5 using the port 50000, and uses the port 50010 to relay the second call downstream RTPT2 and the new second call RTPT6. Relay.

(Media relay server)
With reference to FIG. 7, the media relay server 1 according to the embodiment of the present invention will be described. The media relay server 1 is a general computer including a storage device 10, a processing device 20, and a communication control device 30. Each function shown in FIG. 7 is realized by a general computer executing a media relay program for realizing a predetermined function.

  The storage device 10 stores a media relay program and also stores setting data 11 and recording data 12.

  As shown in FIG. 8, the setting data 11 includes the port number used by the media relay server 1 and the setting data of the call control server, the first communication terminal 7a, and the second communication terminal 7b for the first call and the second call. It is.

  The media relay server port number is a port number used by the media relay server 1 for relaying the first call or the second call.

  The pair port number is set to a port number as a relay destination when terminating communication data. When the port number of the first call is set as the media relay server port number, the port number of the second call is set as the pair port number. When the port number of the second call is set as the media relay server port number, the port number of the first call is set as the pair port number.

  In addition to the pair port number, the media call server port number for the first call is associated with the IP address and port number of the first call control server 2a and the first communication terminal 7a used in the first call. In addition to the pair port number, the media call server port number for the second call is associated with the IP address and port number of the first call control server 2a and the second communication terminal 7b used in the second call.

  When the first call control server 2a fails and the second call control server 2b functions as an alternative, the media call server port numbers for the first call and the second call are the first call and the second call, respectively. The IP address and port number of the second call control server 2b used for two calls are associated with each other.

  The recorded data 12 is audio data while the media relay server 1 terminates the communication data, and is recorded by the recording means 25 described later.

  The processing device 20 includes call control means 21, media control means 22, and call control server failure monitoring means 26.

  The call control means 21 is means for transmitting and receiving an INVITE message and a 200 OK message for establishing a call between the first communication terminal 7a and the second communication terminal 7b. The call control means 21 updates the setting data 11 when receiving a 200 OK message from the first communication terminal 7a and the second communication terminal 7b. In addition, when the first call control server 2a fails and the second call control server 2b substitutes, the setting data 11 is also updated when a 200 OK message is transmitted to the second call control server 2b.

  In the embodiment of the present invention, it is assumed that the first call control server 2a and the second call control server 2b have predetermined combinations of port numbers used for the first call and the second call. For example, when the port number 60000 is used in the first call, the port number 60010 is controlled to be used in the second call.

  As described above, when a combination of port numbers used for the first call and the second call is determined in advance, the call control means 21 specifies a pair of port numbers in the media relay server 1 according to the combination. To do. Furthermore, the media relay server 1 can update the setting data 11 based on the paired port numbers. Further, when the port number that is a pair of the first call and the second call is specified in the setting data 11+, a failure occurs in the first call control server 2a, and the communication data is terminated in the media relay server 1. In addition, the port number of the relay destination can be specified.

  The media control means 22 controls communication data transmitted and received between the first communication terminal 7a and the second communication terminal 7b. The media control unit 22 includes a relay unit 23, a termination unit 24, and a recording unit 25.

  The relay means 23 relays communication data transmitted and received between the first communication terminal 7a and the first call control server 2a in the real-time communication between the first communication terminal 7a and the second communication terminal 7b, and the second communication terminal. The communication data transmitted and received between 7b and the first call control server 2a is relayed. After the failure of the first call control server 2a, when the second call control server 2b becomes able to control real-time communication, the relay means 23 transmits / receives communication data between the first communication terminal 7a and the second call control server 2b. And relays communication data transmitted and received between the second communication terminal 7b and the second call control server 2b.

  The relay means 23 receives a signal addressed to the first call control server 2a from the first communication terminal 7a at the port 50000, transfers the signal to the first call control server 2a, and transfers the signal from the first call control server 2a to the first communication terminal. The signal addressed to 7a is received and transferred to the first communication terminal 7a. The relay unit 23 receives a signal addressed to the first call control server 2a from the second communication terminal 7b at the port 50010, transfers the signal to the first call control server 2a, and transmits the second communication from the first call control server 2a. A signal addressed to the terminal 7b is received and transferred to the first communication terminal 7a.

  When the second call control server 2b functions as an alternative to the first call control server 2a, the relay means 23 receives a signal addressed to the second call control server 2b from the first communication terminal 7a at the port 50000, and The call is transferred to the two-call control server 2b, receives a signal addressed to the first communication terminal 7a from the second call control server 2b, and transfers the signal to the first communication terminal 7a. The relay unit 23 receives a signal addressed to the second call control server 2b from the second communication terminal 7b at the port 50010, transfers the signal to the second call control server 2b, and transmits the second communication from the second call control server 2b. A signal addressed to the terminal 7b is received and transferred to the first communication terminal 7a.

  When a failure occurs in the first call control server 2a, the termination unit 24 terminates communication data transmitted and received between the first communication terminal 7a and the first call control server 2a, and transmits the data to the second communication terminal 7b. The communication data transmitted / received between the second communication terminal 7b and the first call control server 2a is terminated and transmitted to the first communication terminal 7a. After the failure of the first call control server 2a, when the second call control server 2b becomes able to control real-time communication, the termination unit 24 terminates the termination of communication data.

  Here, when the first call control server 2a controls communication between a plurality of communication terminals, the termination unit 24 terminates these communications. At that time, the termination unit 24 refers to the setting data 11 and terminates the communication of the pair of port numbers to be paired and relays the communication data. In the example shown in FIG. 8, the media relay server port number 50000 is paired with 50010. Accordingly, the termination unit 24 receives a signal addressed to the first call control server 2a from the first communication terminal 7a at the port 50000 and transfers the signal to the second communication terminal 7b at the port 50010. The termination unit 24 receives a signal addressed to the first call control server 2a from the second communication terminal 7b at the port 50010, and transfers the signal to the first communication terminal 7a at the port 50000.

  Terminating means 24 operates while second call control server 2b is sending and receiving an INVITE message and a 200 OK message to function as an alternative to first call control server 2a. When the second call control server 2b starts to function as an alternative to the first call control server 2a, the termination unit 24 ends its processing, and the communication data is relayed by the relay unit 23.

  The recording unit 25 stores the recording data 12 in which the communication data is recorded in the storage device 10 while the termination unit 24 terminates the communication data. When the communication data cannot be recorded in the first call control server 2a or the second call control server 2b, the recording means 25 records the call data instead of these servers. The recorded data is stored by a customer management system or the like, and is managed by being merged with the data recorded by the first call control server 2a or the second call control server 2b.

  The call control server failure monitoring unit 26 determines whether or not a failure has occurred in the first call control server 2a, and notifies the media control unit 22 if a failure has occurred. When a failure occurs, the media control unit 22 stops relaying the communication data by the relay unit 23 and terminates the communication data by the termination unit 24. The call control server failure monitoring means 26, for example, transmits a test packet to the first call control server 2a, and a failure occurs in the first call control server 2a when there is no response from the first call control server 2a. Is determined.

  According to the communication system 9 according to the embodiment of the present invention, the first communication terminal 7a and the second communication terminal 7b can receive the IP address of the media relay server 1 regardless of whether or not the first call control server 2a has failed. Send data to the port. Even if a failure occurs in the first call control server 2a, the second call control server 2b may send an INVITE message to the media relay server 1 and sends it to the first communication terminal 7a and the second communication terminal 7b. There is no need. As a result, the time required for switching the call control server can be shortened.

  While the second call control server 2b and the media relay server 1 transmit and receive the INVITE message and the 200 OK message, the media relay server 1 relays the communication data between the first communication terminal 7a and the second communication terminal 7b and needs it. Record accordingly. Thereby, even if a failure occurs in the first control server 1a, it becomes possible to communicate between the first communication terminal 7a and the second communication terminal 7b, and a silent section is hardly generated.

  Thus, the communication system 9 can suppress the influence of the communication failure accompanying the failure of the processing server.

(Modification)
In the modification, the case where the media relay server 1 is multiplexed will be described.

  As shown in FIG. 9, the act media relay server 1a and the standby media relay server 1b have the same IP address and are connected to be communicable with each other. When a failure occurs in the act media relay server 1a, the standby media relay server 1b executes communication data relay or termination.

  A standby media relay server 1b according to a modification will be described with reference to FIG. The act media relay server 1a has the same configuration.

  The standby media relay server 1b provided in FIG. 10 differs from the media relay server 1 according to the embodiment of the present invention described with reference to FIG. The intersystem control unit 27 includes a synchronization unit 28 and a takeover unit 29.

  The synchronization unit 28 shares the life / death information of the act media relay server 1a with the standby media relay server 1b by transmitting / receiving a test signal to / from the act media relay server 1a. The synchronization means 28 also controls the communication data so that it is synchronized with the act media relay server 1a.

  If no signal is received from the act media relay server 1a for a certain period of time, the takeover means 29 considers that the act media relay server 1a has failed, and the standby media relay server 1b changes to the act media relay server 1a. To take over the process. Specifically, the call control unit 21 and the media control unit 22 of the standby media relay server 1b execute processing instead of the units of the act media relay server 1a.

  As described above, according to the media relay server according to the modified example, since the IP addresses are multiplexed by the two servers in common, the processing can be taken over in a very short time. Therefore, the time during which communication between the first communication terminal 7a and the second communication terminal 7b is interrupted is shortened, and a silent section is less likely to occur.

(Other embodiments)
As described above, the embodiments of the present invention and the modifications thereof have been described. However, it should not be understood that the descriptions and drawings constituting a part of this disclosure limit the present invention. From this disclosure, various alternative embodiments, examples, and operational techniques will be apparent to those skilled in the art.

  It goes without saying that the present invention includes various embodiments not described herein. Therefore, the technical scope of the present invention is defined only by the invention specifying matters according to the scope of claims reasonable from the above description.

DESCRIPTION OF SYMBOLS 1 Media relay server 2a 1st call control server 2b 2nd call control server 3a 1st memory | storage device 3b 2nd memory | storage device 4a 1st distribution server 4b 2nd distribution server 5 Load balance server 6 Communication control system 7a 1st communication Terminal 7b Second communication terminal 8 Web server 9 Communication system 10 Storage device 11 Setting data 12 Recording data 20 Processing device 21 Call control means 22 Media control means 23 Relay means 24 Termination means 25 Recording means 26 Call control server failure monitoring means 27 System Control means 28 Synchronizing means 29 Takeover means 30 Communication control device

Claims (7)

A first call control server that controls real-time communication between the first communication terminal and the second communication terminal; a second call control server that controls the real-time communication when a failure occurs in the first call control server; and the first call A communication system comprising a control server and a media relay server connected to the second call control server,
The first call control server
Controlling the real-time communication of the first communication terminal and the second communication terminal;
The media relay server is
In the real-time communication, relays communication data transmitted and received between the first communication terminal and the first call control server, and relays communication data transmitted and received between the second communication terminal and the first call control server. Relay means to
When a failure occurs in the first call control server, communication data transmitted and received between the first communication terminal and the first call control server is terminated and transmitted to the second communication terminal, and the second communication Termination means for terminating communication data transmitted and received between the terminal and the first call control server and transmitting the data to the first communication terminal;
After the failure of the first call control server, when the second call control server can control the real-time communication,
The termination means terminates the termination of communication data;
The relay means relays the communication data transmitted / received between the first communication terminal and the second call control server, and transmits / receives the communication data between the second communication terminal and the second call control server. A communication system characterized by relaying. The communication system includes a standby media relay server having the same IP address as the media relay server,
The communication system according to claim 1, wherein when a failure occurs in the media relay server, the standby media relay server executes relay or termination of the communication data. A first call control server that controls real-time communication between the first communication terminal and the second communication terminal; a second call control server that controls the real-time communication when a failure occurs in the first call control server; and the first call A communication method used in a communication system including a control server and a media relay server connected to the second call control server,
In the real-time communication, the media relay server relays communication data transmitted and received between the first communication terminal and the first call control server, and transmits and receives between the second communication terminal and the first call control server. Relaying communication data to be transmitted;
The first call control server controlling the real-time communication between the first communication terminal and the second communication terminal;
When a failure occurs in the first call control server, the media relay server terminates communication data transmitted / received between the first communication terminal and the first call control server and transmits it to the second communication terminal. And terminating communication data transmitted / received between the second communication terminal and the first call control server and transmitting the data to the first communication terminal;
After the failure of the first call control server, when the second call control server becomes able to control the real-time communication, the media relay server ends the termination of communication data, and the first communication terminal and the second communication terminal A communication method comprising: relaying the communication data transmitted / received between call control servers, and relaying the communication data transmitted / received between the second communication terminal and the second call control server. The media relay server used in a communication system including a first call control server that controls real-time communication between a first communication terminal and a second communication terminal, and a media relay server connected to the first call control server,
In the real-time communication, relays communication data transmitted and received between the first communication terminal and the first call control server, and relays communication data transmitted and received between the second communication terminal and the first call control server. Relay means to
When a failure occurs in the first call control server, communication data transmitted and received between the first communication terminal and the first call control server is terminated and transmitted to the second communication terminal, and the second communication A media relay server comprising termination means for terminating communication data transmitted and received between a terminal and the first call control server and transmitting the data to the first communication terminal. The media relay server is connected to a second call control server that controls the real-time communication when a failure occurs in the first call control server;
After the failure of the first call control server, when the second call control server can control the real-time communication,
The termination means terminates the termination of communication data;
The relay means relays the communication data transmitted / received between the first communication terminal and the second call control server, and transmits / receives the communication data between the second communication terminal and the second call control server. The media relay server according to claim 4, wherein the media relay server is relayed. The media relay server according to claim 4 or 5, further comprising recording means for recording communication data while the termination means terminates communication data.   A media relay program that causes a computer to function as the media relay server according to any one of claims 4 to 6.

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